Laboratory clamps



Feb. 7, 1961 l F P, FRlTCHLE ErAL 2,970,798

LABORATORY CLAMPS Filed 001;. 23, 1956 4 sheets-sheet 1v Feb, 7, 1961 F. P. FRITCHLE ETAL LABORATORY CLAMPS 4 Sheets-Sheet 2 Filed 001'.. 23, 1956 nlllllmllll Feb. 7, 1961 F. P. FRlTcHLE Erm. 2,970,798

` LABORATORY cLAMPs Filed Oct. 23, 1956 4 Sheets-Sheet 3 M1414 /E/lm/M 7%@ Uff@ Feb. 7, 1961 F, P. FRlTcHLE ErAL 2,970,798

LABORATORY CLAMPS Filed 0G13. 23. 1956 4 Sheets-Sheet 4 2,970,798 LABORATORY CLAMPS Frank P. Fritchle, Santa Ana, Calif., and Manning S. Reynolds and Earl K. Takata, Chicago, Ill., assignors to Central Scientific Co., Chicago, Ill., a corporation of Illinois Filed Oct. 23, 1956, Ser. No. 617,772 7 Claims. (Cl. 248-229) Our invention relates to clamps for holding or supporting, for instance, scientific laboratory equipment of various types, and more particularly, to clamps of the type .that are or may be secured to conventional rod-type sup- -ports or rod-like objects commonly found in laboratories where, for instance, experiments or other work in the physical or biological sciences are made.

'the many conventional forms of this type of clamp are characteristic of the rather spasmodic or irregular development of this art. They vary widely in design and function and, generally speaking, they provide no common denominator that lends itself to standardization. Moreover, they tend to be bulky, somewhat fragile in view of their substantial weight, and subject to corrosion. Those of the swivable type generally do not permit one to effectively clamp same against swivelling movement when this is desirable. And, as is well known to those familiar with these devices, the thumb screws, particularly of tne swivelling clamps, always seem to get in the way.

A principal object of the invention is to provide a standardized clamp structure suitable for application to all work which conventional laboratory clamps and other similar devices are now applied.

A further object ofthe present invention is to provide a clamp that can be used for work throughout the physical and biological sciences.

Another object of the invention is to provide a simplied clamp body specially designed for economical mass production procedures.

Still another object of the invention is to provide a set or family of clamps that will provide the laboratory worker with many structural arrangements not possible when conventional clamps are employed.

Yet another object of the invention is to provide va strong, compact, corrosion resistant clamp which will clamp cylindrical or prismatic objects or supports varying in thickness up to the full jaw size of the clamp.

' Still a further object of the invention is to provide a family of clamps having a basic design or common denominator which permit interchangeability of parts while providing or permitting all possible orientation of parts and all desired movements. v

Still a further object of the invention is to provide a general all-purpose clamp family that permits both otfset and coplanar structural arrangements.

Other objects, uses, and advantages will be obvious or become apparent from a consideration of the following description and the drawings, in which like reference numerals are employed to designate like parts.

In the drawings:

Figure 1 is a perspective view of one embodiment of our invention applied to a conventional upright rod type support frequently found in a scientic laboratory, often referred to as a burette support;

Figure 2 is a plan view of the clamp of Figure l, looking in the direction of the arrows of line 2-2 of Figure l;

Figure 3 is a perspective view illustrating another use of the clamp illustrated in Figures l and 2;

Figure 4 is an end elevational view of the clam-p shown in Figures 1 through 3, looking in the direction of the arrows of the line 4--4 of Figure 2;

Figure 5 is a perspective view of a further embodiment of our invention;

Figure 6 is an end elevational view of the clamp shown in Figure 5;

Figure 7 is a perspective view of a swivelling clamp arranged in accordance with the principles of our invention, showing the swivelling end of same detached from the remainder of the clamp;

Figure 8 is a sectional view along the central axis of the clamp shown in Figure 7, showing the parts of same in assembled relation;

Figure 9 is an exploded perspective View of another form of swivelling clamp arranged in accordance with the principles of our invention; Y

Figure 10 is an end elevational view, on a smaller scale, of the right hand end of the clamp as shown in Figure 9;

Figure 11 is a side elevational view of the clamp illustrated in Figure 9, with parts broken away for clarity of illustration, showing several ways in which the clamp may be applied to supports, several of the latter being shown in broken lines;

Figure 12 is a perspective view illustrating still another embodiment of our invention applied to a support similar to that illustrated in Figure 1;

Figure 13 is a perspective view of' the clamp device per se illustrated in Figure 12;

Figure 14 is a plan view of the device illustrated in Figure l2, with the supporting rod being shown in section;

Figure 15 is a cross sectional view along line 15-15 of Figure 14, parts being shown in elevation; and

Figure 16 is an end elevational view of the members shown in Figure 13, looking towards the left .hand end of the device as shown in Figure 13, with a supporting rod shown in broken lines in clamping position.

Referring rst to the embodiment of Figures l through 4, reference numeral 10 generally indicates a form of our clamp which we prefer to term a parallel clamp shown for purposes of illustration applied to a familiar type of laboratory support 12, which generally includes a flat stand 14 having fixed to the upper surface thereof an upright supportingrod 16. The parallel clamp 10 is applied to the rod 16, and is formed to support a supplemental rod 18 or other elements of similar constructions or shapes.

As seen more particularly in Figures 2, 3, and 4, clamp 10 generally comprises a tubular clamp body 20 having rectilinear slots 22 formed in each end of the tube thereof and disposed or oriented parallel to the central axis of the body. The body 20 screw-threadedly receives inclined thumb screws 24.

The slots 22 of clamp 10, as well as the slots of the hereinafter described embodiments of the invention, are of particular significance. lt will be noted that they are defined in part by plane side walls 26 which are disposed substantially parallel to the central axis of the clamp. The side walls 26 merge into plane inclined walls` 28 which converge centrally of the clamp body. The plane surfaces 26 and 28 at each end of the clamp are thus arranged in pairs, and these respective pairs of surfaces.

merge at 30 to form dihedral angles to provide V clamping corners. A thumb screw 24 is screw-threadedly mounted in a leg or proiection 32 opposite a corner 30. The legs or projections 32, of course, are formed by the slots 22 at each end of the clamp bodV 20. As indicated in Figure 2, the thumb screws enter the legs 32 in which they are mounted adjacent their outer edges 33, and are directed towards the angle or corner 36 on the other side of the respective slots. Preferably, the axis of the thumb screw is disposed along the bisector of the angle between the plane surfaces 28 and 26 that the thumb screw opposes. The thumb screws 24 are thus positioned at an angle with respect to the longitudinal axis of the clamp body 20.

1t will be appreciated that only two corner forming surfaces, such as surfaces 28 and 26, are required, and in the illustrated embodiment of the invention, only one thumb screw is mounted at each end of the clamp body, though it is contemplated that a thumb screw could be mounted at each side of each end of the clamp body.

Preferably the legs 32 to which the thumb screws 24 are mounted are flattened at their outer edges as at 36 to aid in the formation of the screw fitting in the clamp body. It will be noted that by angling the thumb screws with respect to the legs 32 in which they are mounted, the purchase that the thumb screws have is materially increased since the thumb screws are in contact with more clamp body screw threading.

In accordance with our invention, the tubular opening 38 of body 20 has an internal diameter that is slightly larger than a supporting rod which it is adapted to receive, as hereinafter described.

In use, a supporting rod 16 may be, for instance, received in a slot 22 after thumb screw 24 is completely withdrawn from the slot 22, and then thumb screw 24 is screwed toward the rod, urging it against the opposing corner or dihedral angle 30 provided by intersecting surfaces 26 and 25. The clamp will then be mounted as illustrated in Figure l, and if desired, supplemental rod 1S may be mounted on the other side of the clamp in a similar manner.

Another useful arrangement employing clamp 2i) is illustrated in Figure 3, wherein the clamp body 24B is disposed in a substantially vertical position, and supplementary rod 1S secured in the upper end of the clamp. The upper end of support rod 16 is then received in tubular opening 38 of clamp body 20, the rod 1S resting against the top of rod 16 wherein rod 16 is fully inserted within body 2t?. Body 20 is thu-s swivelly mounted on top of rod 16 and of course, apparatus can be mounted on either end of rod 18.

It may be added that we call this form of our invention a parallel clamp as the slots 22 are so arranged that when rods are clamped in both of them, they are disposed in parallel relation, as indicated in Figure l.

Figures 5 and 6 illustrate a modified form of the invention which we prefer to term a right angled clamp. The clamp 40 is generally similar to clamp 10 with the eX- cep-tion that the slots 22 of body 20a are at right angles to each other. Thus, rods held in the respective slots 22 will be perpendicular to each other when clamped in place. As the structural features of clamp 4t) are otherwise the same as those of clamp 10, no further description is believed necessary.

Figures 7 and 8 illustrate another form of the invention which we prefer to call a single swivel clamp. Clamp S0 generally comprises a pair of clamp bodies 52 and 54 each of which is generally similar to body 20 and includes slots 22, surfaces'26, 28, and corners 3h, and thumb screws 24, as well as tubular openings 33. Body 52, in the illustrated embodiment, is secured to a ring shaped body 56 formed with a rounded central recess 58v and an annular ange 57. Body 52 screw-threadedl f mounts thumb screw S9. Bodies 56 and 52 may be secured together by screws 6i) or in any other suitable vmanner. and if desired, may be made integral.

Body 54 is formed with a studded end 62 which is in turn formed with an annular groove 64 intermediate of its ends providing shoulders 66 and 68. Shoulders 66 and 68 are of a size to be closely received within the circular recess 58, and are proportioned to prevent sidewise movement of body 54 with respect to the body 52 when these bodies are secured together. As shown in Figure 8, thumb screw S9 forms detent means and is adapted to be screwed inwardly until it is received within the annular groove 64, and this secures bodies S2 and 54 together. Thumb screw 59 may be tightened down against studded end 62 to fix body 54 with respect to body 52, or it may be left loose enough to permit the body 54 to swivel with respect to the body 52 and the body 56, as the occasion demands.

` port 12 as generally indicated inFigure 11.

As indicated at 71 and 73 in Figure 7, the bodies 54 and 56 respectively, may be formed with cooperating indicia for measurement of rotation of body 54 with respect to body 56.

Figures 9, 10, and 1l illustra-te what we prefer to call a double swivel clamp. Clamp generally comprises a pair of clamp bodies 82 and S4, both of which are similar to connecting body 54 of Figure 7, the studded ends 62 of which are swivelly mounted in the angled body 86. Body 86 generally comprises arms 88 and 90 disposed at right angles to each other, and formed with circular recesses 92 which are proportioned to receive the studded ends 62 of bodies 82 and 84. Thumb screws 94 respectively, secure the bodies 82 and 84 t0 the arms 38 and 90.

It will be noted that the arms 88 and 90 are so arranged that supporting rods received within the tubular openings 3S of bodies S2 and 34 and extending from each end thereof, will not interfere with each other. This is because the axial centers of the recesses 92 are positioned to one side of each other a distance equal to at least the rod diameter to be received in the tubular kopenings 38 of the clamp body (see Figure l0). Moreover, since the axes of rotation of the clamp bodies do not intersect and are not parallel, and thus are skew lines, it is apparent that freedom of adjustment is permitted to any position in three dlmensions limited only by the fact that two rods cannot occupy the Same point in space. Thus, both ooplanar and olf-set arrangements are possible with this clamp.

Bodies 82, 84, and 86 may be calibrated for measurement of rotational movement in a manner similar to clamp 50.

Figure l1 illustrates several ways in which supporting rods may be applied to clamp 30. Thus, these rods may be received in slots 22 of the respective clamp bodies, or disposed in openings 38 thereof.

It should be noted that the clamping action of the thumb screws 59 and 94 on bodies 54, 82 and S4 respectively (see Figures 7-11), is especially effective, since the end of the thumb screw bears on the studded ends 62 a substantial distance away from the central axis thereof. This enables these clamps to withstand increased torques without slipping, a distinct advantage over conventional devices.

It should also be noted that the thumb screws of both swivelling forms of our clamps are arranged to avoid interference regardless of how the swivelling elements of the clamps are positioned or moved with respect to the other elements of the clamps.

The embodiment of the invention illustrated in Figures l2 through 16 is applied to clamps of the type disclosed in Sherrill Patent No. 2,269,790, granted January l3, 1942. Clamp generally comprises a clamp body 102 which is generally similar to clamp bodies 54, 82, and 84, except that the studded end is omitted, and the central opening 104 is internally screw-threaded as indicated at 106. Also, body 102 is provided with a rounded surface 108.

The threaded stud of a gripping device, such as that illustrated in said Patent No. 2,269,790, is screwthreadedly received in the tubular opening 104, and in use, the clamp 100 may be secured to rod 16 of sup- Gripper 112 is completely described in said patent, the disclosure of which is hereby incorporated by reference in interests of brevity, but briey it generally includes a pair of gripping arms 114 pivoted to stud 110 by pin 116. Spring 118 urges the arms 114 apart from each other, and nut 120 is employed to cam the arms towards each other about the pin 116. A wing nut 122 is screw-threadedly mounted on stud 110 for movement into engagement with-the rounded surface 108 of clamp body 102 to x gripper 112 with respect to clamp body 102 when the desired positioning has been'arrived at.

It will be appreciated that we have A provided'a set or U family of clamps that permit the laboratory worker to construct many structural arrangements and mechanical movements that heretofore have been dilllcult to do. The basic clamp structure is strong, compact, and llghtweight. The embodiments of the invention as illustrated in Figures through 10 may be secured to support rods in the several ways suggested in Figures 1 through 4, and additionally provide the further functions for which they were designed. All forms of the invention permit a single model to be used for a wide range of applications.

The clamp bodies illustrated may be proportioned for use with any size supporting rods desired. In practice, three eighths inch and one half inch rods are commonly used, while three quarters inch rods are used lessdffrequently; and the clamp bodies will clamp cylindrical or prismatic objects or supports varying in thickness up to the full jaw size of the clamp. The clamp bodies illustrated are particularly adapted to be produced by a casting operation, and they are proportioned to achieve a substantially uniform distribution of metal throughout the casting. The substance from which the clamps are made preferably should be light weight, strong and chemically inert. We prefer to cast the clamp bodies out of aluminum alloy 2314 as specified by The Aluminum Association, while the thumb screws are made from alloy 5052, specified by the same organization. These materials are relatively corrosion resistant.

The foregoing description and the drawings are given merely to explain and illustrate our invention, andthe invention is not to be limited thereto, except insofar as the appended claims are so limited, since those skilled in the art who have our disclosure before them will be able to make modifications and variations therein Without departing from the scope of the invention.

We claim:

4. A clamp as set forth in claim 3 in which a third body having an axial bore therethrough is attached to said second body with the bore of said third body being concentric and connecting with said cylindrical recess of the second body, said third body at the end thereof remote from its attachment to said second body having a screw clamp and an open-ended slot extending trans versely across said remote end of the third body, said last-mentioned screw clamp and slot corresponding in form and location to the screw clamp and slotassociated with said main body.

5. A double swivel clamp for attachment to rod-like objects comprising a pair of rod-clamping members each of which comprises a main body having an axial bore therethrough and formed with an open-ended slot extending transversely across one end of the body and intersecting said bore, said slot being defined in part by flank ing parallel walls symmetrical with respect to said bore and with one of said flanking walls merging with an 'oblique wall extending substantially to the axis of said bore, said oblique wall and the adjoining flanking walll forming an obtuse angle, a screw clamp extending through and having a threaded connection with the other of said flanking walls with the axis of said screw clamp being substantially directed to the apex of said obtuse angle, the other end of said main body having a studded portion generally cylindrical in configuration and concentric l. A clamp for attachment to a rod-like object comprising a main body having an axial bore therefh'ough and formed with an open-ended slot extending transversely across one end of the body and intersecting said bore, said slot being defined in part by flanking parallel walls symmetrical with respect to said bore and with one of said flanking walls merging with an oblique wall extending substantially to the axis of sa`d bore, said oblique Wall and the adjoining flanking wall form'ng an obtuse angle, and a screw clamp extending through and having a threaded connection with the other of said tlanking walls with the axis of said screw clampbeing substantially directed to the apex of said obtuse angle.

2. The clamp as set forth in claim 1 in which said anking walls are spaced apart a distance substantially equal to the diameter of said bore.

3. A clamp for attachment to a rod-like object cornprising a main body having an axial bore therethrough and formed with an open-ended slot extending transversely across one end of the body and intersecting said bore, said slot being defined in part by flanking parallel walls symmetrical with respect to said bore and with one of said flanking walls merging with an oblique wall extending substantially to the axis of said bore, said oblique wall and the adjoining flanking wall forming an obtuse angle, a screw clamp extending through and having a threaded connection with the other of said flanking Walls with the axis of said screw clamp being substantially directed to the apex of said obtuse angle, the other end of said main body having a studded portion generally cylindrical in configuration and concentric with said bore and being formed with an external annular groove spaced from said other end of the body, a second body formed with a generally cylindrical recess receiving said studded portion of said main body, and detent means mounted in said second body and extending radially into said annular groove of said studded portion to retain said studded portion within said second body. and permit relative rotation between said main body and said second body.

with said bore and being formed with an external annular groove spaced from said other end of the body, and a connecting member for joining said two rod-clamping members together, said connecting member comprising rigidly joined arms one being normal to the other with each arm comprising an annular member formed with a generally cylindrical recess receiving said studded portion of said main body,pand detent means mounted in each of said annular members and extending radially into the annular groove of said studded portion of the associated main body to retain said studded portion within said annular member, and permit relative rotation between said main body and said annular members, said annular members being offset with respect to each other so that the axes o f the bores of said main body members do not intersect one another.

6. A clamp for attachment to a rod-like object cornprising a main body having an axial bore therethrough with each end of the body being formed with an openended slot extending transversely across the body and intersecting said bore, each of said slots being defined in part by flanking parallel walls symmetrical with respect to said bore and with one of said flanking walls merging with an oblique wall extending substantially to the axis of said bore, said oblique wall and the adjoining flanking wall forming an obtuse angle, and a screw clamp extending through each of said body ends and having a threaded connection with the other of said flanking walls with the axis of said screw clamp being substantially directed to the apex of said obtuse angle.

7. A clamp as set forth in claim 6 in which the slots at opposite ends of said main body are parallel to each other.

References Cited in the tile of this patent- UNITED STATES PATENTS 790,377 Meston May 23, 1905 1,025,519 Dormandy May 7, 1912 1,064,920 Lovejoy June 17, 1913 1,486,158 Price Mar. 11, 1924 1,782,196 Dalton Nov. 18, 1930 2,269,790 Sherrill Jan. 13, 1942 2,483,152 Reisinger Sept. 27, 1949 2,756,789 Kraus et a1. July 31, 1956 2,763,774 Beach et al Sept. 18, 1956 FOREIGN PATENTS 604,997 Germany Oct. 11, 1934 686,929 Great Britain 3.-....- Feb. 4, 1953 

